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Edogawa, situated in Chiba Prefecture on the eastern fringe of the Tokyo Metropolis, occupies a distinctive position within the Kanto Plain's urban fabric. This densely populated ward lies at the confluence of the Edo River and Tokyo Bay, with coordinates placing it at near-sea-level elevation—typically under 5 meters—creating a flat, low-lying terrain that profoundly influences air quality dynamics. Its geography is characterised by extensive urban development interspersed with riverine corridors and reclaimed land, forming part of Tokyo's eastern expansion zone. Proximity to Tokyo Bay moderates local climates but also exposes Edogawa to maritime influences that can trap pollutants under specific meteorological conditions. The city sits within Tokyo's broader industrial belt, with nearby areas in Chiba and eastern Tokyo hosting manufacturing, port facilities, and energy plants that contribute to regional pollution loads. An urban–rural gradient exists eastward toward more agricultural zones in Chiba, though Edogawa itself is overwhelmingly built-up. This location, sandwiched between central Tokyo's emission sources and bay-area industrial complexes, creates a funnel effect where pollutants accumulate due to limited natural ventilation. The flat terrain inhibits wind dispersal, while the Edo River basin can channel air masses, occasionally concentrating contaminants from upstream urban areas. Surrounding landscape features, including the Boso Hills to the southeast, can influence local wind patterns, but generally, Edogawa's low elevation and dense urbanization make it susceptible to stagnant air episodes, especially when synoptic conditions align with temperature inversions over the Kanto Plain.

Edogawa's air quality follows a distinct seasonal rhythm shaped by Tokyo's temperate climate and regional meteorological patterns. In winter, from December to February, pollution often peaks due to increased heating emissions, frequent temperature inversions that trap pollutants near the ground, and prevailing northwesterly winds that transport contaminants from industrial areas in Saitama and northern Tokyo. Sensitive groups should limit prolonged outdoor exertion during calm, cold mornings when inversion layers are strongest. Spring, from March to May, brings gradual improvement as temperatures rise and ventilation increases, though late spring can see occasional haze from photochemical smog as sunlight intensifies. Summer, from June to August, typically offers the cleanest air due to southerly monsoon winds from the Pacific that disperse pollutants, coupled with convective mixing from heat; however, high humidity can occasionally elevate particulate matter from secondary formation. Autumn, from September to November, sees a transitional period where air quality generally remains moderate until late autumn when cooler temperatures and reduced mixing heights begin to foster accumulation again. Throughout the year, weather hazards like fog are minimal, but stagnant high-pressure systems in winter and early spring pose the greatest risk for pollution buildup. For optimal outdoor activity, favour summer months when ventilation is maximised, and avoid winter mornings when inversions are prevalent. Sensitive individuals, including those with respiratory conditions, should monitor local air quality reports during seasonal transitions and carry preventive medication as advised by healthcare providers.